TY - JOUR
T1 - Partial feminization of hepatic steroid metabolism in male rats after neonatal administration of cyproterone acetate
AU - Gustafsson, J. A.
AU - Ingelman Sundberg, M.
AU - Stenberg, A.
AU - Neumann, F.
PY - 1975
Y1 - 1975
N2 - The metabolism of [4 14C]4 androstene 3,17 dione, [4 14C]5α androstane 3α,17β diol and [1,2 3H]5α androstane 3α,17β diol 3,17 disulphate was studied using the microsomal fraction and the metabolism of [4 14C]4 androstene 3,17 dione was studied using the 105,000 g supernatant fraction of liver from male and female rats aged 5 mth that had been treated with cyproterone acetate before (from day 13 of pregnancy) and after birth (until 3 wk of age). Nearly all sex dependent enzyme activities in the treated male rats were changed in a direction characteristic of female rats: 5α reductase active on 4 androstene 3,17 dione increased in activity whereas 3β and 17α hydroxysteroid reductases and 6β and 16α hydroxylases active on 4 androstene 3,17 dione and 2α, 2β and 18 hydroxylases active on 5α androstane 3α,17β diol decreased in activity. Enzyme activities not under gonadal control, i.e. 3α and 17β hydroxysteroid reductases active on 4 androstene 3,17 dione and 7α hydroxylase active on both 4 androstene 3,17 dione and 5α androstane 3α,17β diol, were not affected by cyproterone acetate. The liver enzyme activities in treated female rats were generally not affected although significant effects were noted in two cases; in one of these (17α hydroxysteroid reductase) a testosterone like effect was observed. The results obtained are probably best explained in the following way: treatment with the anti androgen during the neonatal period results in less efficient imprinting of the hypothalamohypophysial system leading to less pronounced masculine setting of sex dependent enzyme levels and also to a relative androgen unresponsiveness. It is suggested that the biochemical methods used in the present investigation may be used for more exact estimation of the degree of neonatal sexual differentiation of the hypothalamohypophysial system than biological and psychological methods previously availabe.
AB - The metabolism of [4 14C]4 androstene 3,17 dione, [4 14C]5α androstane 3α,17β diol and [1,2 3H]5α androstane 3α,17β diol 3,17 disulphate was studied using the microsomal fraction and the metabolism of [4 14C]4 androstene 3,17 dione was studied using the 105,000 g supernatant fraction of liver from male and female rats aged 5 mth that had been treated with cyproterone acetate before (from day 13 of pregnancy) and after birth (until 3 wk of age). Nearly all sex dependent enzyme activities in the treated male rats were changed in a direction characteristic of female rats: 5α reductase active on 4 androstene 3,17 dione increased in activity whereas 3β and 17α hydroxysteroid reductases and 6β and 16α hydroxylases active on 4 androstene 3,17 dione and 2α, 2β and 18 hydroxylases active on 5α androstane 3α,17β diol decreased in activity. Enzyme activities not under gonadal control, i.e. 3α and 17β hydroxysteroid reductases active on 4 androstene 3,17 dione and 7α hydroxylase active on both 4 androstene 3,17 dione and 5α androstane 3α,17β diol, were not affected by cyproterone acetate. The liver enzyme activities in treated female rats were generally not affected although significant effects were noted in two cases; in one of these (17α hydroxysteroid reductase) a testosterone like effect was observed. The results obtained are probably best explained in the following way: treatment with the anti androgen during the neonatal period results in less efficient imprinting of the hypothalamohypophysial system leading to less pronounced masculine setting of sex dependent enzyme levels and also to a relative androgen unresponsiveness. It is suggested that the biochemical methods used in the present investigation may be used for more exact estimation of the degree of neonatal sexual differentiation of the hypothalamohypophysial system than biological and psychological methods previously availabe.
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U2 - 10.1677/joe.0.0640267
DO - 10.1677/joe.0.0640267
M3 - Article
C2 - 1117237
AN - SCOPUS:0016434609
SN - 0022-0795
VL - 64
SP - 267
EP - 275
JO - Journal of Endocrinology
JF - Journal of Endocrinology
IS - 2
ER -